Prior belt systems have included inflators which are connected directly to the inflator member, such as a belt or belt portion to be inflated (U.S. Pat. No. 5,851,055). The effect of such a direct connection is to subject the fabric of the inflatable member to hot rapidly removing gases. Since such gas discharge causes erosion of the outer layers of the fabric, fabrics of substantial thickness are required Further. inflatable member systems in which the inflator is movable with the inflator member have the drawback that the system including the inflator has an increased weight.
Broadly, the present invention comprises a method and apparatus for receiving gases from an inflator and thereafter briefly storing and supplying such gases to an inflatable member occupant-protection system. Since hot gases of high velocity are discharged into a plenum enclosure before reaching the inflatable member, gas heat and speed dissipation occurs before the gases enter the inflatable member. The plenum member is made of a material resistant to hot gas erosion.
Inflatable members are normally constructed of fabric. In the present invention the inflatable member is not subjected to direct assault of the hot gases, the inflatable member may be constructed of thinner, lighter and more comfortable fabrics. Further, in the practice of the present invention the inflator and its gas supply are stationary thus reducing the weight of the movable portions of the system.
The plenum enclosure also serves as a reciprocal guide for inflatable member end portion which end portion in turn may be attached to the web belt section. Gases residing in the plenum are forthwith supplied to the inflatable member.